©
National Instruments Corporation
13
SCC-SG Series Strain-Gauge Modules User Guide
The following symbols apply to the circuit diagram and equations:
•
R
1
and R
2
are half-bridge completion resistors.
•
R
3
is the active element measuring compression from Poisson effect
(–
νε
).
•
R
4
is the active element measuring tensile strain (+
ε
).
Figure 10 shows how to set up two half-bridge type I configurations with
the SCC-SG03.
Half-Bridge Type II
This section provides information for the half-bridge strain-gauge
configuration type II. The half-bridge type II only measures bending strain.
Figure 8 shows a general half-bridge type II circuit diagram.
Figure 8.
Half-Bridge Type II Circuit Diagram
The following symbols apply to the circuit diagram and equations:
•
R
1
and R
2
are half-bridge completion resistors.
•
R
3
is the active element measuring compressive strain (–
ε
).
•
R
4
is the active element measuring tensile strain (+
ε
).
Figure 10 shows how to set up two half-bridge type II configurations with
the SCC-SG03.
R
1
R
L
R
2
R
L
R
L
R
4
(+ )
R
3
(– )
+
–
–
+
V
EX
V
CH
